Bathurst, J.C. (1987) Critical Conditions for Bed Material Movement in Steep, Boulder-Bed Streams. Proceedings of the Corvallis Symposium, Corvallis, 3-7 August 1987, IAHS Publication 165, 309-318.

has been cited by the following article:

• TITLE: Characterizing Clustering in Boulder Bed Channels and the Impact on Shear Stress Equations

  AUTHORS: Katherine Clancy

  KEYWORDS: Boulder Bed, Shear Stress, Particle Distribution, D84

  JOURNAL NAME: Journal of Water Resource and Protection, Vol.13 No.4, March 26, 2021

  ABSTRACT: Boulders and cobbles are often used in stream restoration projects to increase flow resistance and enhance channel stability and habitat diversity. Particle size metrics determined from the particle distribution are often used as a proxy for shear stress in field equations. Clustering of large particles has been thought to contribute to shear stress, but the effect of clustering is not accounted for in equations that use a representative particle size, such as the D84. In this paper, clustering is defined using the upper tail (≥84%) in a variable called Topsum. The number of clusters, average size of clusters, and shear stress are evaluated using the proposed definition of cluster. Findings suggest that the upper tail represents the roughness height better than the commonly used proxy of D84 for boulder bed streams (streams which have a D84 particle 0.05 - 0.15 meters).